Airtech (Hungtinton Beach, Calif., USA) has developed Dahlar Release Bag 500, a self-releasing multi-layer bagging film for direct contact with prepreg for fabrication of hollow parts. It reportedly exhibits good release of epoxy and polyester resins. Maximum use temperature is 450°F/232°C with a tensile strength of 8702 psi. Dahlar Release Bag 500 is also available in gusseted folding (LFT-G), which makes it easier to position accurately in hollow parts. Upon application of pressure the bag will expand to fit to the shape of the part. This helps ensure even application of internal pressure in cases of small diameter parts, where the insertion of a standard lay-flat tube bagging film can be problematic.